A thug who killed his flatmate by using him as a "human trampoline" has been jailed for life.

Mark Johnstone, 31, and his older brother Martin jumped up and down on helpless victim Robert Kelly, 46, after a vodka binge ended in murder.

They meted out an attack of such ferocity on the former chef that the man living in the flat below thought someone was pounding his ceiling with a sledgehammer.

After the killing, the brothers threw a sleeping bag over Mr Kelly's battered body and went to sleep.

Mark Johnstone showed no emotion as a jury at the Old Bailey unanimously convicted him of murder.

Co-accused Anthony Meenan, 54, who also lived in the flat at the time, was cleared of murder and manslaughter. He told the court he had tried to stop the attack.

Martin Johnstone died in April last year before he could stand trial.

Jurors were told how police discovered Mr Kelly's badly-beaten corpse lying in front of an electric fire in the lounge of the flat in Downland Court, Portslade, Brighton, in January last year. Experts found bootprints all over his body.

A post-mortem examination revealed he had suffered at least 20 impact injuries to his face and head.

He had fractured ribs, collapsed lungs and both his liver and spleen were torn.

Paul Lewis, prosecuting, said: "Mr Kelly was punched, he was kicked and almost certainly was struck with some object."

Anthony Goddard, who lives in the flat below, was watching TV when he heard the row.

Mr Lewis said: "So loud were the noises that his reaction was that someone was using a sledgehammer."

When he was arrested, Mark Johnstone denied having any knowledge of how Mr Kelly had been killed.

But two days later he confided to another brother, John, that Martin was responsible for the attack.

Mr Lewis said: "He said both he and Tony Meenan had tried to stop Martin but he had not listened."

Several weeks after the killing, Meenan of West Hill Road, St Leonards, told police both Mark and Martin Johnstone had attacked Mr Kelly.

Walter Aylen, defending Mark Johnstone, of no fixed address, said: "Drink has been the curse of this still young man's life."